Draw a dependency relational schema diagram for this data. You may assume the following:

Each material item has one or more suppliers. Each supplier may supply one or more items or may not supply any items.

The unit price for a material item may vary from one vendor to another.

The terms code for a supplier uniquely identifies the terms of the sale $($e$.$g$.,$ code $2$ means $10$ percent net $30$ days$).$ The terms for a supplier are the same for all material items ordered from that supplier.

b$)$ Decompose this diagram into a set of diagrams in $3$NF$.$

c$)$ Draw an E$-$R diagram for this situation.